This invention relates to wellbore equipment utilized in conjunction with operations performed in subterranean wells and, in particular, sand control screen assemblies that provide secondary flow capabilities.
During hydrocarbon production from subsurface formations, efficient control of the movement of unconsolidated formation particles into the wellbore, such as sand, has always been a pressing concern. Such formation movement commonly occurs during production from completions in loose sandstone or following the hydraulic fracture of a formation. Formation movement can also occur suddenly in the event a section of the wellbore collapses, thereby circulating significant amounts of particulates and fines within the wellbore. Production of these unwanted materials may cause numerous problems in the efficient extraction of oil and gas from subterranean formations. For example, producing formation particles may tend to plug the formation, tubing, and subsurface flow lines. Producing formation particles may also result in the erosion of casing, downhole equipment, and surface equipment. These problems lead to high maintenance costs and unacceptable well downtime.
Numerous methods have been utilized to control the movement or production of these unconsolidated formation particles during production operations. For example, one or more sand control screen assemblies are commonly included in the completion string to regulate and restrict the movement of formation particles. Such sand control screen assemblies are commonly constructed by installing one or more screen jackets on a perforated base pipe. The screen jackets typically include one or more drainage layers, one or more screen elements such as a wire wrapped screen or single or multi layer wire mesh screen, and a perforated outer shroud. The screens can often incorporate resins and/or tackifiers that help keep the particulates in position or otherwise not produced.
Over time, the screen jackets can become plugged with loose particulates and fines, generally referred to herein as a filter cake, which can slow hydrocarbon production or stop production altogether, especially in significantly plugged locations within the wellbore. To clean the screen assemblies and remove the filter cake, acids or other solvents can be injected into the wells in order to remove the filter cake, after which the screen assemblies are often flushed to ensure proper function once more. The process of cleaning the screen assemblies is costly, and can require a significant amount of valuable rig time during which hydrocarbon production is temporarily stopped.